What is Curiosity?
Curiosity is a robotic spacecraft, also known as a rover, currently exploring the surface of Mars. Curiosity was designed to investigate whether life can exist on the Red Planet. Through its research on Mars, Curiosity will help scientists and engineers plan for future human missions to Mars.
Curiosity is not the first rover ever sent to Mars, but it is the most advanced. Weighing in at 1,982 pounds, Curiosity is about the size of a car. Equipped with 17 cameras, multiple scientific instruments and an innovative landing system, Curiosity carries the most advanced payload of scientific gear ever used on Mars’ surface. The payload is more than 10 times as massive as Spirit and Opportunity, which were earlier rovers that were about the size of a golf cart.
How did Curiosity land on Mars?
Curiosity launched into orbit on at 10:03 a.m. EST on Nov. 26, 2011, aboard an Atlas V from Cape Canaveral Air Force Station, next door to Kennedy Space Center. Curiosity’s journey to Mars was a little over eight months and it landed successfully on the floor of Gale Crater on Aug. 6, 2012.
While the previous Mars rovers all had a similar landing strategy, Curiosity's landing was the first of its kind.
First, the spacecraft was packed into a shell that protected it during the journey to Mars and during its descent to the surface of the planet, when temperatures were as hot as 3,800 degrees Fahrenheit. As the shell holding the spacecraft zoomed to the surface of Mars at about 900 mph, a parachute - the biggest ever built for a space mission - was released and acted like brakes to slow the spacecraft down. The spacecraft's protective shell fell away and a special device holding the rover fired its eight jets and released Curiosity on a bungee-like apparatus called the "sky crane." The entire process, called the entry, descent and landing, took about seven minutes, coined by NASA as Seven Minutes of Terror, prior to landing.
How will Curiosity search for signs of life on Mars?
Curiosity will act as a mobile science laboratory while on Mars. It will use a drill and scoop at the end of its robotic arm to gather soil and powdered samples of rock interiors, then sieve and parcel out these samples into analytical laboratory instruments inside the rover.
Some of the 10 tools are the first of their kind on Mars, such as a laser-firing instrument for checking the elemental composition of rocks from a distance, and an X-ray diffraction instrument for definitive identification of minerals in powdered samples.
Curiosity’s Instruments
A suite of instruments named Sample Analysis at Mars analyzes samples of material collected and delivered by the rover’s arm, plus atmospheric samples. There are tools to identify a wide range of organic (carbon containing) compounds and to determine the ratios of different isotopes of key elements. Isotope ratios are clues to understanding the history of Mars’ atmosphere and water.
Mounted on the arm, the Mars Hand Lens Imager takes extreme close-up pictures of rocks, soil and, if present, ice, revealing details smaller than the width of a human hair. It can also focus on hard-to-reach objects more than an arm’s length away.
An X-ray diffraction and fluorescence instrument called CheMin also examines samples gathered by the robotic arm. It is designed to identify and quantify the minerals in rocks and soils, and to measure bulk composition.
Also on the arm, the Alpha Particle X-ray Spectrometer for Mars Science Laboratory determines the relative abundances of different elements in rocks and soils.
The Mars Science Laboratory Mast Camera, mounted at about human-eye height, images the rover’s surroundings in high-resolution stereo and color, with the capability to take and store high-definition video sequences. It can also be used for viewing materials collected or treated by the arm.
An instrument named ChemCam uses laser pulses to vaporize thin layers of material from Martian rocks or soil targets up to 23 feet (7 meters ) away. It includes both a spectrometer to identify the types of atoms excited by the beam, and a telescope to capture detailed images of the area illuminated by the beam. The laser and telescope sit on the rover’s mast and share with the Mast Camera the role of informing researchers’ choices about which objects in the area make the best targets for approaching to examine with other instruments.